This invention relates to an apparatus for and method of depositing adhesives, and more particularly to an apparatus capable of the precise deposition of adhesive strips on a length or piece of material, such as metal, plastic or fabric.
In particular, the manufacture of garments from fabric materials has traditionally involved numerous sewing procedures. These sewing procedures were formerly carried out manually by individual tailors wielding needles and thread. The advent of the sewing machine signaled a vast improvement in the art, however, extensive human interaction is still necessary in virtually every phase of garment fabrication since sewing procedures are not readily adaptable to automation. In particular, numerous manual operations are required in the fabrication of components for a garment. For example, the construction of pockets alone involves many time-consuming manual operations which tend to boost the manufacturing cost for the entire garment. In an attempt to eliminate these time-consuming and costly manual operations, there recently has been some interest in the use of adhesive connection techniques as a replacement for stitched seams. However, the proficient utilization of adhesive materials in garment fabrication requires an accurate means for positioning adhesive material at a predetermined location on fabric material which has not heretofore been available, other than manually.
The present invention comprises an apparatus for depositing adhesives which overcomes the foregoing and other problems long since associated with the prior art. In accordance with the broader aspects of the invention, a ribbon of adhesive is directed along a predetermined path adjacent to a length or piece of material for deposition. The adhesive ribbon can comprise a substance responsive to heat, radiation, pressure, or ultrasonic vibration. A precise length of adhesive formed from the ribbon is metered into proximity with the material before activation and engagement to attach the strip of adhesive thereto. Consequently, utilization of the invention permits predetermined strips of adhesive to be attached at precise locations to a length or piece of material prior to subsequent fabrication operations. The apparatus functions on an automatic basis, thus eliminating many heretofore required manual trimming and positioning operations associated with the use of adhesives in various operations. While the invention is particularly suited to the deposition of adhesives onto fabric, it will be understood that the invention can be utilized with metals, plastics or other materials.
In accordance with more specific aspects of the invention, a ribbon of adhesive is drawn from a roll of ribbon. The adhesive ribbon may include a backing on one side of the adhesive. In a first embodiment of the invention, adhesive ribbon with a backing on one side thereof is engaged between measuring and feed rollers and directed into positioning structure. Prior to entering the positioning structure, separation means responsive to the measuring roller traverses and separates the adhesive layer of the ribbon from the backing to provide an adhesive strip of preselected length. Subsequent rollers draw the adhesive ribbon into positioning structure located adjacent a length or piece of material onto which the adhesive is to be deposited. With the strip of adhesive disposed between the backing and the length of material, a movable head is actuated to press the material and the adhesive strip into engagement with the positioning structure, thereby securing the adhesive strip to the adjacent material. The head itself can be heated or ultrasonically vibrated to activate the adhesive, or an outside source of radiation or heat could be used, if desired. The deposited adhesive strip is disconnected from the backing strip, by which the next strip of adhesive is drawn into the positioning structure.
In a second embodiment of the invention, measuring and feed rollers engage and advance the adhesive ribbon between fixed and movable blades into positioning structure adjacent a length or piece of material. The presence of a backing on one side of the adhesive ribbon is not required for the operation of this embodiment. After positioning of the adhesive ribbon, a movable portion of the positioning structure extends to simultaneously shear the ribbon and to press the material and sheared strip of adhesive into engagement with a stationary head. If desired, the material can then be advanced around a series of rollers to remove any backing from the attached adhesive strip. In both of the first embodiments, the material can be advanced through the apparatus at any desired orientation relative thereto. Thus, the first two embodiments of the invention function to deposit substantially straight strips of adhesive at precise locations on a piece of material.
In a third embodiment of the invention, an apparatus for depositing strips of adhesive is mounted on steerable post structure. The incoming adhesive ribbon is engaged by a feed and metering pulley which is rotatably mounted in the post structure. The adhesive ribbon is directed toward a revolving wheel which is drivingly interconnected with the feed pulley. Means are provided for precision stopping and starting of the adhesive ribbon in the apparatus, if desired. Preferably, separation means responsive to the feed pulley are provided to separate the adhesive ribbon into strips of preselected length. The revolving wheel includes a circumferential recess for receiving and guiding the adhesive strip into engagement with the underlying material. The adhesive strip is activated as it is guided into engagement. The wheel itself can be heated or ultrasonically vibrated to activate the adhesive, or an outside source of radiation or heat can be used, if desired. In the third embodiment, the apparatus can be steered relative to the adjacent material, which affords directional capability whereby relatively longer adhesive strips can be precisely deposited in linear or curvilinear fashion.